Re: 2002 3.8L Mustang Heat Problem
car still cooling fine after swap? no leakes in pass. floor ? there is a eleitric switch which connects in a line from somewhere off raditor and goes to your heator cord under your dash along with a return line which comppletes a circle. a fan blows heat transfered from the radiator thru a sm radiator. if the switch is close it will be cold hince no hot water from radiator to warm
it may be opening and closeing back should be easy to find im not sure where it is on your car.
go to auto zone look in there chiltons book under cooling diagrams and see where it is loacated